The subject matter disclosed herein relates to a power plant and, more particularly, to a combined cycle power plant or a cogeneration power plant.
A combined cycle power plant consists of several pieces of major equipment. These include the gas turbine(s), a steam turbine and heat recovery steam generators (HRSG). The gas turbine produces power and exhaust energy. The gas turbine exhaust energy is captured by the HRSG and is used to convert water to steam, which is then expanded in the steam turbine to produce additional power.
During startup operations of the combined cycle plant, the gas turbine(s) feed exhaust energy to the HRSG to produce steam but the rate of change of gas turbine exhaust energy to the HRSG causes thermal stresses to the HRSG components. These stresses can lead to damage that impacts the life of the HRSG.
Therefore, a primary limitation in fast starting combined cycle power plants is the additional life expenditure per start that the HRSG experiences. In fact, in spite of the financial benefits of starting up power plants faster, the impact on HRSG life expenditure makes customers wary of technologies that help combined cycle plants startup faster.